November 16, 2010

Probe Collects First-Ever Asteroid Dust Samples

A deep space probe that returned from a seven-year mission earlier this year contained the first ever samples of asteroid dust to be brought back to Earth, Japanese scientists confirmed Tuesday.

In an official statement, the Japan Aerospace Exploration Agency (JAXA) said that electron microscope observations and analysis of the samples confirmed that material contained in one of two compartments of the Hayabusa spacecraft "were identified as rocky particles"¦ most of them were judged to be of extraterrestrial origin, and definitely from Asteroid Itokawa."

The sizes of the particles were "ultra-minute" and "mostly less than 10 micrometers," JAXA officials added. During a news conference, Japanese science and technology minister Yoshiaki Takagi called the feat "a world first and a remarkable accomplishment," according to the AFP.

Officials with JAXA believe that the discovery could answer many questions about the origins of the universe, telling Reuters, "There is so much that humans don't know, such as how the Moon was formed"¦ but research, not just into these particles but into other findings, could provide us with hints on how the solar system and the planets were formed."

The Hayabusa probe, which returned in July following a seven year voyage into the deep space, had originally been designed to search for peanut-sized rocks, according to Richard Van Noorden, author of the Nature.com blog "The Great Beyond."

However, due to technical problems--including a glitch in which the $200 million probe had lost contact with Earth for nearly two months--"the presence of even tiny asteroid particles is a triumph for Hayabusa," he added. While the sample capsule was successfully received, the Hayabusa spacecraft itself was destroyed during its re-entry attempt.

As for the particles themselves, according to BBC News Science Correspondent Jonathan Amos, they "contain the minerals olivine, pyroxene and plagioclase."

"Although common on Earth, these particles are said to be quite different in the Hayabusa samples, in their relative abundances and in their atomic composition," added Amos. "These minerals are also common in certain meteorites, as is the mineral troilite (an iron sulphide) which has also been identified."

---

Image 2: What's that unusual looking spot on asteroid Itokawa? It's the shadow of the robot spacecraft Hayabusa that took the image. Credit: ISIS, JAXA